Multiple punch and die sets



I Feb. 17, 1959 w. J. SMITH MULTIPLE PUNCH AND DIE sE'rs 2 Sheets-Sheet1 Filed March 2, 1956lllllIll|Ill]Illlllllllllllllflllllllllllllllllllllllfl] a! 12, as, 35

FIG?

Feb. 17, 1959 W. J. SMITH MULTIPLE PUNCH AND DIE SETS Filed March 2,1956 2 Sheets-Sheet 2 lNVENTOR W J. SMITH ETTURNEV UnitedStates Patent2,873,627 MULTIPLE PUNCH AND DIE SETS William J. Smith, Lavallette, N.J., assignor to Western Electric Company, Incorporated, New York, N. Y.,a corporation of New York Application March 2, 1956, Serial No. 569,142

4 Claims. (Cl. 76-107) not warranted. To produce these perforated platesand panels without the costly conventional punch and die sets,commercially known individual punch and die units may be employed. itis-possible to set up successive groups of these units but, due to thephysical size of the punch and die holders and their hold-down extensionmembers,

numerous successive arrangements of the units are often required to makea single plate or panel. In one instance, the number of holes requiredin a panel made ,it necessary to use seventeen different settings of theindividual punch and die units. This required considerable time for thesetting up operations and either .a large number of presses; if one isprovided for each setting or the added dismantling time if fewer pressesare available; The numerous settings multiplied not only the timerequired for perforating each plate or panel, but also thepossibility ofinaccuracies in the locations of the holes.

Objects of the present invention are a punch and die set, including anovel die, which is simple and economical in structure and readily andaccurately manufacturable, and a highly efiicient method of making thesame.

One of the greatest problems in making punch and die sets, particularlywhen a multiplicity of punches and dies are to be employed, is thekeeping of the dimensional changes in the die structure during thehardening process Within tolerable limits. tion, according to theobject,;this problem is solved by cutting the die. plate containing amultiplicity of die cavities inv sections to divide the die cavitiesinto groups and to minimize the possibility of variations in the diesegments, particularly the respective positions of. the die cavitiesduring the hardening process.

In following the method in this embodimentof the invention, the punchand die sets for the multiplicityof dif-C ferently arranged punches anddies may be made readily at low cost. More, specifically, the methodcomprises initially connecting a punch plate, a stripper plate, a dieplate and a back-up plate for the die, in their respective positions bytwo dowel pins extendingthrough all of the plates. Spacers are disposedin'out-of-way positions between the stripper plate and the die plate toreceive another plate to serve as a stop for tools used for enlargingthe holes inthepunch plate and the stripper plate and protect the dieplate. The drilling, boring and reaming operations may-be performed in ajig boring machineto produce the holes inthe various plates of thedesiredsizes and, in this manner, assuring accurate positioning andaligning of the various groups of holes in the plates. Subsequently,after the holes in the die plate have been completed and while the dieplate is connected through the initial locating pins on the back-upplate, the die In'one'embodiment of the inven.

J sdesired materials.

plate is marked to divide it into sections. .After marking the die platetwo additional sets of holes for dowel pins are drilled in the markedsections of the die plate where selected groups of die holes are to beincluded in predetermined sections of the die. Also, holes are drilledand counter-sunk in the different sections of the die plate for mountingscrews and aligned drilled holes are tapped in the back-up plate. Thedie plate is now ready to be cut along the marked lines by, for example,a band saw, to divide the die plate into its plurality of sections. Thevarious sections are heat-treated to produce the necemary hardness andreturned to the backing plate where, through the aid of the additionalpairs of dowel pins, the die sec tions may be disposed in theirrespective positions on the back-up plate and secured in place by themounting screws. After mounting the back-up plate on a die shoe whichhas been provided with the necessary larger holes for the die openingsthe shoe may be mounted in the conventional manner on the bed of apress. The punch plate, *after receiving a. series ofpunches in theholes thereof, is fixedly mounted on the punch holder which is followingdetailed description when considered in conjunction with theaccompanying drawings, wherein:

Fig. l is an isometric view of the upper portion of the punch and dieset mounted on a punch holder of a punch press;

Fig. 2 is an isometric view of the lower portion of the punch and dieset mounted on a die shoe which in turn is mounted on a bed of thepress;

Fig. 3 is a front elevational view illustrating a group of plates inposition for producing the necessary holes therein;

Fig. 4 is an isometric view of a jig boring machine wherein the numerousholes of the plates may be processed, and

Fig. 5 is a top plan view of a plate produced by the present embodimentof the punch and die set.

Referring now to the drawings, the species of punch and die setsselected to illustrate the invention begins with fourv plates ofsuitable sizes and thicknesses and produced from These plates include apunch plate 10, a stripper plate 11, a die plate 12 and a backup plate14. In carrying out the steps of the method, these plates are initiallyclamped together for the drilling and reaming of aligned holes 15, 16,17 and 18 respectively therein at desired positions away from wheresubsequentholes are. to be processed in the plates to receive dowel pins19 to secure ,the plates in their respective positions. Through the aidof a jig boring machine 20 (Fig. 4) of a commercially known type whereina work support 21 may be moved forwardly, rearwardly. or to either side,calibrated distances through the actuation of hand cranks 23 and 24, theconnected plates 14 11, 12 and 14 may be moved relative to the axis ofthe tool holding chuck 25 forcarrying out successive drilling, boringand reaming operations 1, to produce the necessary holes in the plates.It is to be understood that the holes in the die plate 12 are smallerthan the other aligned holes. For example, the holes in the back-upplate 14 arelarger than their die holes to allow'escapement of the punchparts, the holes the punch *plate' 10 are to be of the desired size toire mov ably receive their respective punches and the holes in thestripper plate 11 are to be of desired sizes for free movement of thesmaller sizes required for the dies or die holes, after which the holesin the plates and 11 may be enlarged by. changing. the tools 27 of thejig boring machine 20. To make possible an eflicient carrying out ofseveral method steps in the production of the various holes in theplates, spacing bars 28 are positioned adjacent the ends of the platesbetween plates 11 and 12 and, during subsequent boring and reamingoperations performed on plates 10 and 11, an'auxiliary plate 29 may bepositioned to rest. on the die plate 12 serving to stop movementof. thevarious tools 27 used'in subsequently boring the holes in the plates iiiand 11 and thereby protect the dieholes.

After all the drilling, boring and reaming operations have beencompleted on the four plates, plates 10, 11 and 12 areremoved from thedowel-pins 19 and the dowelpins are'employed in mounting the back-upplate 14 on a die Shoe 30. When these two members 14 and 30' are mountedin the jig boringv machine, the back-up plate acts as a'guide fordrilling the necessary holes in the die'shoe. At the same time: theholes in the back-up plate are enlarged.

The punch plate 10 is ready to receive the necessary punches inthevarious holes thereof and for mounting in the conventional manner ona punch plate 32' which is fixed to a ram of a press and provided withconventional bushings 33 for guide rods 34 of the die shoe 30. Thestripper plate may be mova'bly connected to the punch plate in aconventional 'manner and spaced from the punch plate by suitably knownspring means causing the stripper plate to function in the conventionalmanner during the operating cycles of the press.

The die plate 12 is returned to the back-up plate 14 and l'ocated in itsproper position thereon through the aid of the dowel pins 19. The nextstep of the method includes marking the upper surface of the die platein any suitable manner to divide all of the die holes-into selectedgroups so that the die plate 12 subsequently may be divided into aplurality of smaller plates to reduce thenumber of dieholes or cavitiesas equally as possible in smaller areas. After the die plate is marked,through the aid of the jig boring machine 20, a pair of holes 36 isdrilled in each marked section of the die plate, continuing the drilledholes into the'b ack-up plate to receive dowelpins 37. Following thisstep and before mounting the dowel-pins 37 in place, additional holesare drilled and counter-sunk in the different sections for mountingscrews 38 andcorresponding holes are drilled and tapped in the backup.platel ifor the mounting screws.

When these steps of the method are completed, the die plate 12 isremovedfrom the back-up plate 14, the back-up plate is provided with thevarious dowel-pins 37 and, through the aid of suitable means such as aband saw, the die plate is cut along the marked linesto divide the dieplate into the plurality of section 12. These sections pass through ahardening step of the method wherein they are heat-treated to produce aRockwell hardness R. C. 62-63. After the hardening step of the methodhas been completed, the various sections 12? are returned to theirrespective positions and, through the aid ofthe dowel-pins 37, they arelocated accurately on the backup plate 14 where they are firmly securedin place by the mounting screws 38. The back-up plate 14 is secured inplace on the die shoe which is then mounted on the bed; of the press.The method is completed and this specie of the punch and'die setis'complete, installed, and ready for operation. 7

It is apparent, by following the steps of the method, that the cost ofproducing the punch and die set is, low, particularly when consideringthe numerous perforating operations which are performed simultaneously,enabling the-production of plates or panelswithmany perforations--therein regardless of how closely they are positioned with respect toeach other. Furthermore, by reducing the single die plate to a pluralityof smaller sections containing smaller groups of die holes, prior tocarrying out the hardening step of the method,- keeps the dimensionalchanges which may take place during this step within tolerable limits.Furthermore, should damage occur to any portion of the overall die, onlythat section of the die wherein the damage occurs need be replaced,leaving all of the other sections to continue their usefulnessthroughout the life of the die and reducing maintenance of the punch anddie structure to a minimum. Also, should changes be made, such as theremoval or the addition of other punches and dies, these changes may bemade readily.

It is to be understood that the above described arrangements are simplyillustrative of the application of the principles of the invention;Numerous other arrangements may be readily devised by those skilled inthe art which will embody the principles of the invention and fallwithin the spirit and scope thereof.

What is claimed is:

l. The method of forming a multiple die comprising securing a die plateand a back-up plate together, drilling a plurality of aligned pairs ofholes in the plates, dividing the die plate into a plurality ofindividual members, heattreating the die members to harden them, andsecuring the die members in their respective positions to the 'backupplate.

2. The method of forming a multiple die comprising securing a die plateand a back-up plate together, drilling a plurality of aligned pairs ofholes in the plates, marking the die plate to divide the holes of thedie plate into smaller groups, cutting the die plate along the markingsto divide the die plate into a plurality of individual die,

members, heat-treating the die members to harden them and'securing thedie members in their respective positions to the back-up plate.

3. The method of forming a multiple die comprising securing a die plateand a backup plate together, drilling a plurality of aligned pairs ofholes in the plates, marking the dieplateinto areas for groups oftheholes therein,

drilling holes through the die plate'and into the back-up plate forsecuring means for each area, cutting the die plate along-the markingsto divide the die plate into individual members for the areas,heat-treating the die members to harden them, and securing the diemembers in their'respective positions-on the'back-up plate.

4; The methodof forming a multiple punch and die set from a punch plate,a stripper plate, a die plate and a back-up plate for the dieplatecomprising securing the plates "against displacement relative toeach other in stacked formation with space between the stripper plateand the die plate, drilling a plurality of aligned: sets of holes in theplates, boring the holes'in' the punch plate'and the stripper plate toenlarge them fortheir respective punches, andinserting a stop platebetween the stripper plate and the die plate prior to the boring step.

References Cited in the file of this patent UNITED STATES PATENTS1,070,889 Hartog' Aug. 19, 1913 2,186,799 Boker Jan. 9, 1940' 2,275,706Wales Mar; 10, 1942 2,543,527 Gyuris Feb. 27, 1951' 2,553,615 Wales May22,. 1951 24 .21 .2 6

